Drying wood is known in the field of wood preparation and preservation. There is a broad spectrum of processes that are utilized to dry wood. One such process occurs naturally to wood maintained at atmospheric conditions, such as with the aging of cut logs on a wood pile. This drying reduces the water content of the wood, while the wood remains susceptible to decay and cellular degeneration due to fungal pathogens, for example. Other drying techniques utilize heated chambers, such as kilns, maintained at elevated temperatures, such as those between about 40 degrees C. (105 degrees F.) and about 90 degrees C. (195 degrees F.), to more quickly dry wood. Wood dried in this manner is conventionally utilized as lumber, such as for construction projects and the like. Other conventional drying processes utilize high-temperature steam to dry wood at temperatures of between about 90 degrees C. (195 degrees F.) and about 150 degrees C. (302 degrees F.). This temperature level provides shorter drying times and more dimensionally-stable lumber, as compared with the previously discussed processes. Such conventional lumber is typically marketed for sale having a water content of between about 15 percent and about 18 percent. Once such lumber is in use in an ambient environment for some time, such as in a frame house, the wood has a water content of between about 10 percent and about 15 percent.
Another conventional wood drying process utilizes even more elevated temperatures, such as between about 150 degrees C. (302 degrees F.) and about 215 degrees C. (420 degrees F.) to alter the color of the wood itself. The upper limit on the heating can be higher than the 215 degrees C. (420 degrees F.) noted above, as long as the temperature remains below the charring temperature of the treated wood. Such processing is conventionally utilized to create the appearance of stained wood, without the use of chemical stains. Because such wood is superheated to elevated temperatures, much of the water content is removed from the wood, bringing water levels in the heat-treated wood to between about two percent and about ten percent. Although this process is known in the art of wood preparation and preservation, the wood product created by the process has not been used conventionally as a medium for monitoring or controlling termites. Moreover, conventional techniques and knowledge regarding termite monitoring and controlling teach that this wood would not be of use for monitoring and controlling termites. First, wood having a higher water content, such as between about 10 percent and about 20 percent is conventionally thought to be more attractive to termites. Second, heat-treating wood in this manner produces a heat-treated wood product that is less hygroscopic than untreated wood or wood dried at lower temperatures. As such, conventional wisdom regarding termite feeding would indicate that such wood would not be attractive to termites because even with additional water available (such as with a below ground installation), the heat-treated wood will resist the absorption of water. Without absorbing water, the conventional wisdom goes, the termites will not be interested in feeding.
In contrast with this conventional thinking regarding termite food selection and contrary to past understanding and teaching regarding termite wood preferences, the present invention utilizes such heat-treated wood with relatively lower levels of water and less hygroscopy than conventionally treated wood with unexpected success as a food source and attractant for termites. Additional benefits include enhanced resistance to microbiological attack and an increased amount of extractable compounds attractive to foraging termites. A termite monitoring and control method utilizing this heat-treated wood thus provides unexpected benefits over more conventional wood-based termite stations.